Multi-Functionalized Carbon Nano-onions as Imaging Probes for Cancer Cells

• Published in: Chemistry : a European journal Vol. 21; no. 52; pp. 19071 - 19080
• Main Authors: Frasconi, Marco, Marotta, Roberto, Markey, Lyn, Flavin, Kevin, Spampinato, Valentina, Ceccone, Giacomo, Echegoyen, Luis, Scanlan, Eoin M., Giordani, Silvia
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 21.12.2015; WILEY‐VCH Verlag; Wiley Subscription Services, Inc
• Subjects: Aqueous solutions; Biocompatibility; Biomedical materials; Cancer; Carbon; Carbon - chemistry; Cellular; Chemistry; Confocal; Cytotoxicity; electron microscopy; Endosomes; Fluorescein; fluorescence; folate receptor; Folate Receptor 1 - chemistry; Folate Receptor 1 - metabolism; Folic acid; Humans; Imaging; Localization; Medical imaging; Microscopy, Electron, Transmission; Nanomaterials; Nanoparticles; Nanostructure; Nanostructures - chemistry; Nanotechnology; Onions - chemistry; Position (location); Probes; surface chemistry; Toxicity; Transmission electron microscopy; Tumor cell lines; electron microscopy; folate receptor; nanomaterials; surface chemistry; fluorescence
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201503166

Carbon‐based nanomaterials have attracted much interest during the last decade for biomedical applications. Multimodal imaging probes based on carbon nano‐onions (CNOs) have emerged as a platform for bioimaging because of their cell‐penetration properties and minimal systemic toxicity. Here, we describe the covalent functionalization of CNOs with fluorescein and folic acid moieties for both imaging and targeting cancer cells. The modified CNOs display high brightness and photostability in aqueous solutions and their selective and rapid uptake in two different cancer cell lines without significant cytotoxicity was demonstrated. The localization of the functionalized CNOs in late‐endosomes cell compartments was revealed by a correlative approach with confocal and transmission electron microscopy. Understanding the biological response of functionalized CNOs with the capability to target cancer cells and localize the nanoparticles in the cellular environment, will pave the way for the development of a new generation of imaging probes for future biomedical studies. Class onion: Surface functionalization of small multi‐shell fullerenes (diameter of 5 nm) with imaging and cell recognition capabilities was accomplished. This integrated system allows the targeting of cancer cells and the detailed analysis of its pathway. The localization of the imaging probe in the cell environment was analysed by correlation of confocal and electron microscopy (see figure).